How Solar PV Panels Work

Electricity is simply a flow of electrons running around a closed circuit. So how do we create a flow of electrons using a solar PV panel and sunshine?

Well the internal workings of solar panels are quite complex, but I’ll have a go at explaining. Don’t worry too much if you don’t understand the next paragraph!

The photons which make up light bombard the solar PV panel and dislodge electrons from their resting places. These electrons randomly flow around inside the silicon leaving holes in their place. Due to the laws of physics, the electrons then recombine. During all of this activity, energy is released and is what we capture and is called the photovoltaic effect.

Or if you are like me and learn by pictures, then this might make more sense:

1) The atoms in the silicon crystals in the solar PV panels are surrounded by electrons:

2) The sunlight falls on the crystals of silicon and “electrons” are ejected and bounce around randomly:

3) This leaves behind an electron hole:

4) When an electron finds this hole and recombines, it creates energy which we can capture as electricity:

And that is my best effort at explaining how the solar PV panels on your roof take sunlight in and spit electricity out. How did I do?

The electricity from the solar PV panels is ‘captured’ by heavy duty wires and fed into a box of electronics called an ‘Inverter’. The primary purpose of the inverter is to boost the fairly feeble flow of electricity (known as ‘low voltage DC’) into nice, clean and reliable, high voltage 240V AC electricity that is compatible with both your household appliances and the electricity grid.

Any of the electricity that comes out of this inverter that is not used by your house and gadgets will, by the natural forces of physics flow through your meter and out into the wider world via the national electricity grid.